Fastening means for crankcase vent valve

ABSTRACT

An improved means and method for fastening a crankcase ventilating valve in an internal combustion engine comprising an outlet body of heat stabilized plastic receiving therein the metal valve housing of a crankcase vent valve with said housing having both a straight knurled portion and a locking ridge to provide adequate locking of the valve housing in the outlet body.

United States Patel n., 3,594,020

[72] Inventor William E. llhlert [56) References Cited 7 l N ggwiddl- UNITED STATES PATENTS @55d A r 264 w69 1,994,784 3/1935 Porzel 285/239 [45] Patented h5 'mwn 2,l39,745 l2/l938 Goodall 285/259 X mi Assi nee mgm ne um 2,374,225 4/1945 Melsom 285/259 X g enwogd i 3,263,699 8/1966 Givier et al, 123/119 X 3,359,960 12/1967 Pittsley 123/119 Primary Examiner- Dave W. Arola l ttomey-Stevens, Davis, Miller and Mosher [54] FAS'llENlING MEANS lFOlR CMANKCASE VENT VALVE s Cnaims, 3 Drawing Figs. I ABSTRACT. Aun lrnproved rneanslandl method for tastenmg'a crankcase Ventilating valve ln an mtemal combustion engine [52] U.S. Cl Y 285/239, comprising an outlet body of heat stabilized plastic receiving 285/174, 29/521, 123/119 v therein the metal valve housing ofa crankcase vent valve with [5l] lm Cl Fl6l33/00 said housing having both a straight knurled portion and a [50] Field of Search .I 285/239, locking ridge to provide adequate locking of the valve housing lin the outlet body.

GASES l W y' n TO INTAKE MANlFOLD PATENIEUJUIQOIQII- 3,594,020

\ l2 TO INTAKE MANIFOLD INVENTOR w l? WILLIAM E. EHLERT GASES FROM CRANKCASE BY I MMM/@wf ATTORNEYS liidb'fllihllltlflii lt/lllEAtltlS iFUilt ClltAhlllfCASE VIENT VAlLi/lE During the development of the two-piece plastic and metal cranltcase ventilation valve, it was discovered that the difference in the coefficient of thermal expansion between the metal valve housing and plastic outlet body made it difficult to lock these parts together at the elevated temperatures that the valve was eirposed to in the engine compartment during normal running of the engine. The initial samples were fluid tightly fastened together at room temperature, but at hot engine idling temperatures the plastic housing could be easily rotated about the steel valve casing. This clearly indicated that the valve was not fluid tight in the housing and that therefore the valve would not accomplish its purpose of smog control by reciiculating blowby accumulating in the engine cranlccase.

The general type of valve used in combination with the present invention has been described in US. Pat. No. 3,263,699 to .lohn D. Givler et al. issued Aug. 2, 1966, and generally comprises a metal valve housing having a valve seat and a spring-biased valve therein. The inlet end of the valve housing is mounted on the engine, for example on the rocker arm cover, and the outlet end is connected to the mainfold through an outlet body and conduit.

The present invention provides an improved means for fastening together the valve housing and outlet body of crankcasc vent valves by having an outwardly directed locking ridge and an adjacent straight knurled portion on the valve housing for engaging with and tightly holding the valve housing fast in the outlet body under all temperature conditions.

lt is an object of the present invention to provide a means and method for securely fastening the outlet end of a crankcase vent valve to an outlet body which will overcome the abovenoted deficiencies of the pn'or art.

it is a further object ofthe present invention to produce a fastening means which is readily and economically produced.

lt is also an object of the present invention to produce a fastening means which allows rapid assembly of the valve housing and outlet body.

rlllrie means for accomplishing the foregoing objects and other advantages, which will be apparent to those skilled in the art, are set forth in the following specification and claims, and rire illustrated in the accompanying drawings dealing with a basic embodiment of the present invention. Reference is made now to the drawings in which:

lTlG. l is vertical section through the outlet body;

llG. 2 is an end view of the outlet body; and

lFllG. 3l is a vertical section ofthe assembled outlet body and valve with the valve being shown only partly in section.

The plastic outlet body lllll is comprised of substantially two main portions. Portion lll is a cylindrical portion which receives the valve housing itself. Portion llil; is an integral tubular portion intersecting the larger cylindrical portion ll at substantially a right angle and serves to connect the valve to a conduit leading tothe intake manifold. The tubular portion l2 has an outwardly directed flange i3 at its outer end thereof. The cylindrical portion lill has an inwardly directed taper ld at the bottom end thereof. The taper llil makes the lower part of cylinder lill more resilient so that it can be pushed over protrusions of valve housing more easily.

Turning to lFlG. 1i, the assembly of the invention is shown with the engine crankcase being generally indicated at l5. The crankcase has an orifice therein into which a resilient grommet llo is lined. The valve body i7 includes a groove portion lil which is received in the gromrnet llo between annular flanges il@ and The outlet body llil is fitted on the valve housing through a combination of the locking ridge 2l and a straight knurled portion 22, for example 9o pitch straight knurl, which is adjacent to but spaced from the locking ridge. Both the locking ridge and the straight knurled portion engage with, and to some extent penetrate into, the sidewalls of the cylindrical portion llll of the outlet body to tightly hold the valve housing therein. A flexible tube or conduit 23 is connected to the tubular portion l2, and annular flange i3 serves to hold'the tube in position.

The valve itself has been generally indicated as having a valve body Ztl, a spring biasing means 25, and a valve seat 26. The operation of the valve is known and operates according to the principles as described in the above-mentioned patent 3,263,699 to Givler etal.

lt should be noted that the upper end of the valve housing has a portion 27 which has a reduced diameter so that an annular chamber 23 is formed between the outlet body and the valve housing. The lower edge of the reduced diameter portion 2'7 is preferably in substantial alignment with the tubular portion l2 so that there will be free passage of gases through the valve, annular chamber and tubular portion. The reduced diameter portion 2'7 is connected to the main portion of the valve housing by an inclined surface 229, which surface may be either linear or arcuate (as shown).

The outer diameter of the main portion of the valve housing is slightly larger than the interior diameter of the cylindrical portion lill of the outlet body. This, of course, assures a tight fit when the parts are assembled. The inclined portion 29 aids the assembly of parts by camming the cylindrical portion lll open as the valve housing is forced in.

The material used for the outlet body is preferably a heat stabile material such as Zytcl-lOS, a product of E. l. Dupont De Nemours Co., Wilmington, Delaware. Zytel is heat stabilized 66 nylon containing a stabilizer to retard einbrittlement at high service temperatures. lt has good thermal stability but poor electrical properties.

The present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are to be therefore embraced therein.

lclaim:

l. A means for forming a fluid tight connection between the valve housing and outlet body of cranikcase vent valves at elevated temperatures, which connection is solely formed by said valve housing and outlet body, comprising an outlet body having a cylindrical portion with a tubular portion extending at right angles therefrom said cylindrical portion having a bore therein and a valve housing having a radially outwardly directed locking ridge and a straight knurlcd portion adjacent to but spaced from said locking ridge, said straight knurled portion and locking ridge having an outer diameter greater than the inner diameter of said cylindrical bore portion, said linurled portion and locking ridge engaging with and tightly holding said valve housing fast in said cylindrical bore portion of said outlet body, said outlet body providing a substantially smooth outer surface when assembled with substantially no deformation of its outer surface at least in the area of said ridge and knurled portion.

2. The device according to claim ll wherein said outlet body is formed of a heat stabilized 66 nylon having high thermal stability.

3. The device according to claim ll wherein the valve housing has a bore therethrough and a portion of reduced diameter connected to the remaining portion by an inclined surface, an annular chamber formed by said cylindrical portion of said outlet body and the reduced diameter portion of said valve housing, said annular chamber, valve housing bore and tubular portion being in fluid communication with each other.

o. The device according to claim 3 wherein said outlet body has an interior diameter less than the outer diameter of the remaining portion of said valve housing, said inclined surface serving to cam said outlet body open during assembly.

5. A method for forming a fluid tight connection between the valve housing and outlet body of a two-piece crankcase vent valve at elevated temperatures which relies solely on said housing and outlet body to form said connection, comprising forming a bore in said outlet body, forming on said vent valve housing a locking ridge having an outer diameter larger than the diameter of said bore forming a straight kriurled portion body being plastically deformed on the interior of said bore only by said locking ridge and knurled portion and presenting a substantially smooth outer surface with substantially no deformation of its outer surface at least in the area of said ridge and knurled portion. 

1. A means for forming a fluid tight connection between the valve housing and outlet body of crankcase vent valves at elevated temperatures, which connection is solely formed by said valve housing and outlet body, comprising an outlet body having a cylindrical portion with a tubular portion extending at right angles therefrom said cylindrical portion having a bore therein and a valve housing having a radially outwardly directed locking ridge and a straight knurled portion adjacent to but spaced from said locking ridge, said straight knurled portion and locking ridge having an outer diameter greater than the inner diameter of said cylindrical bore portion, said knurled portion and locking ridge engaging with and tightly holding said valve hOusing fast in said cylindrical bore portion of said outlet body, said outlet body providing a substantially smooth outer surface when assembled with substantially no deformation of its outer surface at least in the area of said ridge and knurled portion.
 2. The device according to claim 1 wherein said outlet body is formed of a heat stabilized 66 nylon having high thermal stability.
 3. The device according to claim 1 wherein the valve housing has a bore therethrough and a portion of reduced diameter connected to the remaining portion by an inclined surface, an annular chamber formed by said cylindrical portion of said outlet body and the reduced diameter portion of said valve housing, said annular chamber, valve housing bore and tubular portion being in fluid communication with each other.
 4. The device according to claim 3 wherein said outlet body has an interior diameter less than the outer diameter of the remaining portion of said valve housing, said inclined surface serving to cam said outlet body open during assembly.
 5. A method for forming a fluid tight connection between the valve housing and outlet body of a two-piece crankcase vent valve at elevated temperatures which relies solely on said housing and outlet body to form said connection, comprising forming a bore in said outlet body, forming on said vent valve housing a locking ridge having an outer diameter larger than the diameter of said bore forming a straight knurled portion having an outer diameter larger than the diameter of said bore adjacent to but spaced from said locking ridge and forming adjacent said knurled portion an end portion of said housing of reduced diameter connected to the rest of the housing by an inclined surface and mounting said housing in said outlet body bore, said inclined surface serving to cam open said outlet body to receive said valve housing with said bore, said outlet body being plastically deformed on the interior of said bore only by said locking ridge and knurled portion and presenting a substantially smooth outer surface with substantially no deformation of its outer surface at least in the area of said ridge and knurled portion. 